As is known in the art, the formation of an image according to a silver halide photographic method requires a projection light-exposure process to form a latent image, and a development processing process to convert the latent image thus-formed into the corresponding silver or dye image. See, for example, Mees & James, The Theory of the Photographic Process, 4th ed., 1977.
The formation of a latent image according to projection light-exposure process results from extremely small changes in silver halide crystals when considered from a chemical standpoint, and the latent image itself is essentially unstable. Over a period from the time of the projection light-exposure process to the time of the development processing process, the intensity of the latent image is liable to decrease. This phenomenon is generally called "latent image fading". Usually the latent image fading results in disadvantageous reduction of the photographic sensitivity. The progress of the latent image fading varies generally depending on the conditions under which an exposed light-sensitive element is stored; for example, when the exposed light-sensitive element is stored at a high temperature, the latent image fading is generally significant, whereas when stored at a low temperature, it is generally less significant.
One simplified method for overcoming disadvantages resulting from the latent image fading is to carry out the development processing immediately after the projection light-exposure, and a second simplified method is to store the exposed light-sensitive element at a low temperature. Although these methods are the easiest from a chemical standpoint, they are often not convenient for the user. Negative elements and reversal elements are often allowed to stand at room temperature for several months after projection light-exposure before they are subjected to development processing. Even positive elements for duplication are sometimes allowed to stand for several months.
It is therefore desirable to prepare a silver halide photographic light-sensitive element which is capable of preventing the fading of latent image by application of a specific procedure in the course of the production thereof. In order to obtain such light-sensitive elements, various methods have heretofore been proposed.